With this patch we can now do things like verify a x509 cert against a x509_ca
then extract its pubkey and test a message signature.
cert = crypto.x509_cert()
cert:from_pem(server_cert)
kpub = cert:pubkey()
message = 'Hello world'
verified = crypto.verify('md5', message, signature, kpub)

inlines at best are a micro optimization and all modern compilers figure
it out. On GCC 4.4 the exact same code is output with and without the
inline. And as a bonus this all should compile under Windows now.

Initial commit of code to verify an x509 cert against a CA.
Here is an example usage of the API:
ca = assert(crypto.x509_ca())
ca:add_pem(ca_cert)
assert(ca:verify_pem(cert_to_verify) == true, "failed to verify good cert")